ディピリン・コバルト・イミドスによる触媒C-Hアミネーション
Yunjung Baek1, Theodore A Betley1
1Department of Chemistry and Chemical Biology , Harvard University , 12 Oxford Street , Cambridge , Massachusetts 02138 , United States.
Journal of the American Chemical Society
|April 25, 2019
まとめ
この研究は,効率的なC−Hアミネーション触媒を促進する新しいコバルト (I) シンソンを導入する. コバルト (III) イミド複合体は,特にピリジンと協調すると,C−H結合機能化のための反応性および触媒周回力が向上する.
科学分野:
- 有機金属化学
- カタリシス
- 合成化学
背景:
- 触媒用途の新型移行金属複合体の開発
- C−H機能化反応におけるコバルト複合体の探求
- コバルトイミド種の反応性の理解
研究 の 目的:
- 新しいコバルトを合成し,特徴づけること.
- コバルト (III) イミド複合体のC−Hアミネーションにおける反応性を調査する.
- コバルト触媒によるC−Hアミネーションの仕組みを明らかにする.
主な方法:
- カリウムグラフィットを用いてコバルト (II) コンプレクスをコバルト (I) シントンに還元する.
- コバルト (I) 複合体をアルキルアジドで処理して,コバルト (III) イミド複合体を形成する.
- 構造確認のための単一結晶X線 difraktion.
- ピリジン調整を研究するためのH NMR定位実験.
- 反応のメカニズムを調査するために,運動同位体効果実験を含む運動学的な研究.
主要な成果:
- 新しいコバルトの合成を成功させました.
- 三座標コバルト (III) アルキルイミド複合体の形成, (ArL) Co ((NR).
- ピロリジン形成につながる分子内C-Hアミネーションの観察.
- ピリジンのコバルト (III) イミド複合体への調整は,C-Hアミネーションの反応性と触媒の周回性を高めます.
- 動力学的研究は,C-Hアミネーションの2段階のラジカル経路を示唆している.
結論:
- 新型コバルト (I) シントンは,コバルト (III) イミド複合体の汎用的な前駆体である.
- ピリジン結合コバルト (III) イミド複合体は,C-Hアミネーションの非常に効果的な触媒である.
- 反応性の向上は,ピリジン調整時により高いスピン状態の集団と減少した結晶領域に起因する.
- この研究は,コバルト触媒によるC-Hアミネーションに根幹経路を通じて機械的洞察を提供している.
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